Madrid's slump in the Champions League coincided with the departure of Cristiano Ronaldo to Juventus, which happened after Madrid beat Liverpool in the 2018 Champions League final.
Asensio had already hit the woodwork before he opened the scoring in the 41st minute. Benzema added a second goal with a header in the 73rd.
Bale returned to Tottenham on loan in September after seven years away and has had a mixed season with form and fitness issues dominating his second spell in north London.
Kroos slipped a short pass through two defenders to leave Benzema alone to beat goalkeeper Iván Villar in the 20th.
Madrid defeated Atalanta 3-1 on Tuesday to advance 4-1 on aggregate after two consecutive eliminations in the last-16.
The club said Monday that the Belgium playmaker has a muscle injury in his right leg, the latest of a series of problems that have kept him from playing much lately.
Karim Benzema, Sergio Ramos, Marcelo and Eden Hazard are all expected to be available for the second leg at the Alfredo Di Stéfano Stadium.
Benzema’s late brace earned Madrid a 2-1 win over Elche on Saturday, cutting into Atlético’s lead at the top after it was held 0-0 at 10-man Getafe.
Elche defender Dani Calvo headed the visitors in front in the 61st minute at Alfredo Di Stéfano Stadium.
Ramos is ready to return from a left knee injury that has sidelined him since mid-January, but his commitment to Real Madrid is not assured with his contract set to expire on July 1.
Benzema scored in the 87th minute after Luis Suárez's early goal for Atlético at the Wanda Metropolitano Stadium.
Just as it looked as if Atalanta would hold on for a draw, Mendy received the ball outside the area after a corner and curled a shot into the right side of the net from 20 yards.
The striker, who has netted 17 goals in all competitions this season, has still not recovered from a slight tear in his left abductor muscle.
The hard-fought win came after Atletico Madrid fell at home to Levante 2-0; Barcelona take on Cadiz today.
Madrid's third straight league victory left Zidane’s team five points behind Atlético, which won 2-1 at Granada on Saturday and has two games in hand.
Benzema and Ferland Mendy scored in the second half as Madrid went on to win for the third time in four games in the Spanish league.
Varane scored twice in the second half to help the defending champions come from behind to win at last-placed Huesca 2-1 in the Spanish league on Saturday.
A year and a half later, many in Spain believe Hazard's ill fortune with injuries mean he will never be the star he was in the English Premier League.
Madrid said the 73-year-old Pérez is asymptomatic and tested positive after a routine test. No other details were released.
None of Real Madrid and Barcelona made a deadline day transfer with the latter mired in political turmoil, being led by a caretaker board that can't make many decisions regarding transfers.
Top News
Latest News
